ICIJ's deputy director, Marina Walker Guevara, sent me a list of Greek names they had extracted from the data and some extra clues on the material.

She told me that I had two choices: either travel to a country in Eastern Europe to search the data myself now, or wait until November to get remote help from another colleague. Two months was too long to wait. A few days later I travelled to Eastern Europe.

An ICIJ colleague showed me how to search the millions of records. During the first few hours I was totally frustrated; I had to check different tables with names and codes; I had to cross check numbers, shareholders, sham directors and addresses; and read hundreds of emails. And time was pressing - I couldn't occupy his desktop and office forever. My aim was to track down all of the offshore companies connected with Greeks in the next three days and to be at the airport on time. I still am not sure if I tracked them all.

Back in Greece the crosschecking continued. With the help of another ICIJ colleague in Spain, Mar Cabra, new aspects of the Greek offshore world were revealed. The stories behind the complex moves of the directors and shareholders unraveled slowly, and some of them were expanding outside the country.

Via the ICIJ forum, Vlad Lavrov from Ukraine, Roman Shleynov from Russia, and Frederik Obermaier from Germany provided valuable answers to my questions about the findings. In one way or another, the problems arising during my investigations were solved by ICIJ's advanced infrastructure and the unprecedented solidarity among my colleagues in this project.

Except for one.

The deeper I went into the stories, the more I confronted opaque obstacles that were not only in the secretive offshore world but in the Greek onshore reality as well.

In my efforts to find out how many of the 107 offshore entities of Greek interest in the ICIJ data were unknown to our tax authorities, I submitted a formal request to the Ministry of Finance of the list of foreign companies registered in Greece.

I still haven't received an answer. Although the list with the foreign entities should be publicly accessible, it wasn't. That's not an exception, it's the rule that applies in Greece to tons of information which should be available to the public.

From sources inside the ministry I was able to access the list of registered offshore companies "unofficially." This lead me to discover that the Greek tax authorities knew of the existence of only four out of the 107 offshore entities in the ICIJ data.

Another wall of opacity appeared while searching two bond transactions via an offshore entity of Greek interests. Due to the fact that the transactions took place over the counter, there was no way to find out who had bought the bonds. And it was one of the most interesting purchases I have ever seen: the buyer paid almost double the price the bonds had sold for just four months earlier, while the company's stock price had remained at the same levels.

Still, after seven months of research into the secretive offshore world, I think that I have only scratched the surface. I know there is a lot more work that has to be done. And, with the help of my colleagues around the world, this scratching may become digging.